New Laser-Welding Boosts Productivity

TRAVERSE CITY, MI "It's not evolutionary; it's revolutionary," says Frank DiPietro, describing new laser-welding technology he says boosts productivity nine-fold. It already is catching on quickly in Germany and Japan but, so far, not in the U.S., he says. A long-time General Motors Corp. manufacturing executive who retired in 1990, DiPietro now has his own laser manufacturing consulting firm, L.A.S.E.

It already is catching on quickly in Germany and Japan but, so far, not in the U.S., he says.

A long-time General Motors Corp. manufacturing executive who retired in 1990, DiPietro now has his own laser manufacturing consulting firm, L.A.S.E. Inc., and is a vocal cheerleader when it comes to extolling the virtues of lasers.

DiPietro, a perennial fixture at the Management Briefing Seminars here, in an interview with Ward's, predicts the budding laser technology will transform the way auto makers and their suppliers weld body components, because potentially huge gains in productivity can be achieved.

The technology already is being used by DaimlerChrysler AG in its Sindelfingen, Germany, assembly plant to weld firewall and other engine compartment stampings and also is employed by a major auto maker in Japan, he says.

Key to the technology are sophisticated scanners containing reflectors that can be programmed to guide high-powered laser beams to produce up to three welds in just a single second.

By comparison, one spot weld using resistance-welding technology commonly used by auto makers worldwide takes three seconds.

"That's a nine-fold increase, with all of the economic gains you get with higher throughput," he says. Moreover, it soon may be possible to do five welds per second, he adds.

Robotic laser welding has been around since the early 1990s, but with the addition of scanning devices the number of welds per pass rises dramatically, DiPietro underscores.

Lasers basically weld without directly contacting metal and need to be applied only to one side of the two sides being joined. By contrast, resistance welding requires joining from both sides of the stampings and direct contact with the metal, which takes more time.

DiPietro says two laser scanning methods currently are being used. In one, the scanner remains stationary, and the stampings to be welded pass under it. In the other, the scanner is attached at the end of the robot's arm. In both cases the procedure takes only one second to make three spot welds, he says.

"Everybody is jumping all over the place (about the technology) in Europe and Japan, but not here," he says. "Why is it we invented the laser beam in 1960, but it takes the Germans and Japanese to apply it?"